Illumination device, system and method for manually adjusting automated fading of color temperature changes to emulate exterior daylight

ABSTRACT

An illumination device, system and method are provided herein for emulating sunlight along a daytime or nighttime locus. Sunlight is emulated depending on the path length of the sun relative to a structure containing the illumination device and system. One or more illumination devices can be grouped together and perform the sunlight emulation along the locus by producing different color temperatures throughout the day by all illumination devices within that group producing the same color temperature changes throughout the day. Moreover, a particular advantage of the preferred embodiments is the ability to manually change at any time the emulated natural sunlight output from the one or more groups of illumination devices and advantageously change the color output more so at certain times than at other times by simply actuating a trigger on a dimmer associated with a virtual or physical keypad.

RELATED APPLICATIONS

This application is related to co-pending applications filedconcurrently herewith under Ser. No. 15/264,775, entitled “IlluminationDevice, System and Method For Manually Adjusting Automated PeriodicChanges In Emulation Output”, and Ser. No. ______, entitled“Illumination Device, System and Method For Manually Adjusting AutomatedChanges In Exterior Daylight Among Select Groups Of Illumination DevicesPlaced In Various Rooms Of A Structure.”

BACKGROUND OF THE INVENTION 1. Field of the Invention

This invention relates to illumination devices comprising light emittingdiodes (LEDs) whose color temperature and/or brightness automaticallychanges throughout the daytime or nighttime and, when lighting changesare manually applied, the color temperature can advantageously changebased on time of day.

2. Description of the Relevant Art

The following descriptions and examples are provided as background onlyand are intended to reveal information that is believed to be ofpossible relevance to the present invention. No admission is necessarilyintended, or should be construed, that any of the following informationconstitutes prior art impacting the patentable character of the subjectmatter claimed herein.

Illumination devices, sometimes referred to as lighting fixtures,luminaires or lamps include incandescent illumination devices,fluorescent illumination devices and the increasingly popular lightemitting diode (LED) illumination devices. LEDs provide a number ofadvantages over traditional illumination devices, such as incandescentand fluorescent lighting fixtures. Primarily, LED illumination deviceshave lower power consumption, longer lifetime, are constructed ofminimal hazardous materials, and can be color tuned for differentapplications. For example, LED illumination devices provide anopportunity to adjust the chromaticity (e.g., from white, to blue, togreen, etc.) or the color temperature (e.g., from “warm white” to “coolwhite”) to produce different lighting effects.

An illumination device can include a multi-color LED illuminationdevice, which combine a number of differently colored emission LEDs intoa single package. An example of a multi-color LED illumination device isone in which two or more different chromaticity of LEDs are combinedwithin the same package to produce white or near-white light. There aremany different types of white light illumination devices on the market,some of which combine red, green and blue (RGB) LEDs, red, green, blueand yellow (RGBY) LEDs, phosphor-converted white and red (WR) LEDs, RGBWLEDs, etc. By combining different chromaticity colors of LEDs within thesame package, and driving the differently colored LEDs coated with ormade of different semiconductor material, and with different drivecurrents, these illumination devices can mix their chromaticity outputand thereby generate white or near-white light within a wide gamut ofcolor temperatures or correlated color temperatures (CCTs) ranging from“warm white” (e.g., roughly 2600 K-3700 K), to “neutral white” (e.g.,3700 K-5000 K) to “cool white” (e.g., 5000 K-8300 K). Some multi-coloredLED illumination devices also enable the brightness and/or color of theillumination to be changed to a particular set point. These tunableillumination devices should all produce the same color and colorrendering index (CRI) when set to a particular brightness andchromaticity (or color set point) on a standardized chromaticitydiagram.

A chromaticity diagram maps the gamut of colors the human eye canperceive in terms of chromaticity coordinates and spectral wavelengths.The spectral wavelengths of all saturated colors are distributed aroundthe edge of an outlined space (called the “gamut” of human vision),which encompasses all of the hues perceived by the human eye. The curvededge of the gamut is called the spectral locus and corresponds tomonochromatic light, with each point representing a pure hue of a singlewavelength. The straight edge on the lower part of the gamut is calledthe line of purples. These colors, although they are on the border ofthe gamut, have no counterpart in monochromatic light. Less saturatedcolors appear in the interior of the figure, with white and near-whitecolors near the center.

In the 1931 CIE Chromaticity Diagram shown in FIG. 1, colors within thegamut 10 of human vision are mapped in terms of chromaticity coordinates(x, y). For example, a red (R) LED with a peak wavelength of 625 nm mayhave a chromaticity coordinate of (0.69, 0.31), a green (G) LED with apeak wavelength of 528 nm may have a chromaticity coordinate of (0.18,0.73), and a blue (B) LED with a peak wavelength of 460 nm may have achromaticity coordinate of (0.14, 0.04). The chromaticity coordinates(i.e., color points) that lie along the blackbody locus 12 obey Planck'sequation, E(λ)=Aλ⁻⁵/(e^((B/T))−1). Color points that lie on or near theblackbody locus provide a range of white or near-white light with colortemperatures ranging between approximately 2500 K and 10,000 K. Thesecolor temperatures are typically achieved by mixing light from two ormore differently colored LEDs. For example, light emitted from an RGBLEDs may be mixed to produce a substantially white light with a colortemperature in the range of about 2500 K to about 5000 K. Although anillumination device is typically configured to produce a range of whiteor near-white color temperatures arranged along the blackbody curve(e.g., about 2500 K to 5000 K), some illumination devices may beconfigured to produce any color within the color gamut triangle formedby the individual LEDs (e.g., RGB).

At least part of the blackbody locus 12 is oftentimes referred to as the“daytime locus” corresponding to the Kelvin scale of color temperaturesof daytime. For example, as shown in FIG. 2, several bounding boxes 14a, 14 b, 14 c and 14 d are shown illustrative of color temperaturestargeted to emulate daytime sunlight throughout the day. For example, 14a, 14 b, 14 c and 14 d are chromaticity regions along the daytime locusof blackbody locus 12 (shown in dashed line) corresponding to targetcolor temperatures in Kelvin of 6000 K, 4000 K, 3000 K and 2300 K,respectively. For example, the daytime locus color temperatures of 6000K can emulate blue sky noontime, 4000 K can emulate a less blue mixturewith some yellow overcast sky, 3000 K can emulate a mixture ofpredominant yellow with some red morning sky, and 2300 K can emulatepredominant red with some yellow sunrise sky, similar to the differencesbetween natural white, cool white and warm white color temperatures.

Some illumination devices allow color temperatures to be changed byaltering the ratio of drive currents supplied to the individual LEDchains. The drive currents, and specifically the ratio of drivecurrents, supplied to different colored LED chains can be changed byeither adjusting the drive current levels (in current dimming) or theduty cycle (in PWM dimming) supplied to one or more of the emission LEDchains. For example, an illumination device comprising RGB LED chainsmay be configured to produce a warm white color temperature byincreasing the drive current supplied to the red LED chain anddecreasing the drive currents supplied to the blue and/or green LEDchain.

The color rendering index (CRI) is what defines the overall color orcolor appearance, and the CRI can be defined by the luminous flux (i.e.,lumen output or brightness) and chromaticity. The brightness andchromaticity, or when mixed, the color temperature, can often form thetarget settings that change, due to changes in drive current,temperature and over time as the LEDs age. In some devices, the drivecurrent supplied to one or more of the emission LEDs may be adjusted tochange the brightness level and/or color temperature setting of theillumination device. For example, the drive currents supplied to all ofthe LED chains may be increased to increase the lumen or brightnessoutput from the illumination device. In another example, as noted above,the color temperature setting of the illumination device may be changedby altering the ratio of drive currents supplied to the LED chains. Asnoted above, an illumination device comprising RGB LEDs may beconfigured to produce “warmer” white light by increasing the drivecurrent supplied to the red LED chain and decreasing the drive currentssupplied to the blue and/or green LED chain.

A need exists for an illumination device that can produce a differentcolor or color appearance defined by brightness and chromaticitythroughout the day, including evening and nighttime hours. It would bedesirable to emulate a daytime locus, extending to nighttime, of one ormore illumination devices configured in interior spaces of a structure.Periodic changes to the brightness as well as the chromaticity whichforms the color temperature of one or more groups of illuminationdevices within one or more rooms is needed based on timing signals thatare desirably sent periodically throughout the day. The desired timingsignals can be sent from a timer remote from one or more groups ofillumination devices in order to dynamically change the colortemperatures so as to track, or correspond with, the emulated colortemperatures external to the structure, and specific to outdoor sunlightor possible lack thereof.

There further remains a need for such an illumination system and methodthat need not rely upon sensor outputs in order to periodically changethe color temperature output from a single illumination device or one ormore groups of illumination devices. Dynamic changes in emulated colortemperatures are selectively applied without use of sensor, but insteadthrough use of time of day signals applied on a room-by-room basis. Thisproves advantageous and applicable to improved illumination systems thatdo not and cannot rely upon sensor outputs to periodically change colortemperature output. Still further, it is desirable that whenever a taskis needed that involves a change in color temperature output from one ormore illumination devices, brightness can advantageously be changedmanually to override the emulated sunlight, or lack thereof, output ofcolor temperatures produced by the LEDs. Similar to the desired timerfor producing times of day, output at regular periodic times, andcorresponding color temperature changes in response to those times ofday output, the desired illumination system can alter the dynamic andautomatic emulated sunlight output by manually changing the brightnessof all illumination devices within a group to produce differing changesin color temperature output depending upon the time of day in which themanual adjustment occurs. Advantageously, therefore, it is desirable tomanually change the color temperatures relative to the time of day, andpossibly more so during certain times of day than at other times. Forexample, when the emulated sunlight output mimics a higher colortemperature near noon time, manual changes to brightness when taskingoccurs will not substantially affect the high color temperature neededto maintain a more realistic noontime sunlight emulation. Yet, it isdesirable to manually change the lower color temperature outputs duringsunrise and sunset more so than at noontime, even though the brightnesschanges the same amount as noontime. It is therefore desirable to takeadvantage of the relationship between color temperature as a function ofboth the time of day and brightness so as to achieve task dimming (orreverse dimming) and resulting daytime emulation inside a structure thatis more consistent with the actual sunlight occurring outside thestructure. The emulation and manual override should be desirably appliedto various groups of illumination devices within the structure. Forexample automatic emulation within a group of illumination deviceswithin a bedroom should be different from that of a kitchen, and themanual override in each room should also be different due to differenttasks needed to be performed in those rooms.

SUMMARY OF THE INVENTION

The following description of various embodiments of an illuminationdevice, system and method for dynamically and automatically controllingchanges in color temperature throughout the day or night, and manuallyoverriding the automatically changing color temperature is provided. Themanual override of task dimming can occur at any time of day and,preferably, the change in color temperature resulting from a manualchange to the automatically changing color temperature (eitherincreasing or decreasing the color temperature depending on the desiredtask) can effectively and advantageously maintains a truer emulation tothe actual sunlight changes occurring outside as a function of the timeof day or night.

According to one embodiment, an illumination device is providedcomprising a plurality of LED chains, where each chain can be configuredto produce illumination for the illumination device at a chromaticityconsistent with a chromaticity setting. For example, each chain can beone of the primary chromaticity colors, such as red, green or blue.Moreover, a chain can also have a chromaticity consistent with a whitechromaticity setting. The illumination device can also comprise a drivercircuit coupled to the plurality of LED chains. The driver circuit isconfigured to generate a drive current to each of the chains and, basedon the drive current supplied to those chains, the drive current canautomatically change a color temperature output from the illuminationdevice as a function of the time of day. For example, if the ratio ofdrive currents to the LED chains is modified at periodic times, thatmodification can occur automatically based on time outputs from, forexample, a timer.

The automatic modification or change made to color temperature is onethat does not involve actuation of a trigger, such as a slider, on auser interface of a remote controller. Unlike the manual overrideinvolving a change in intensity value sent from a remote controller toan interface or a dimmer to a controller, the automatic change to thecolor temperature occurs through parameters or set-points, pre-existingas stored content within memory of one or more illumination devices, andare invoked when the illumination device or devices receives time of daysignals sent from the remote controller. A manual override must involveuser actuation of a trigger on a user interface, whereas automaticchanges to color temperature occur when the appropriate time of daysignal is periodically and automatically sent without any user actuationupon a trigger.

The illumination device can further comprise a control module coupled tothe driver circuit for sending a brightness value resulting from a taskdimming function, for example. The brightness value is sent to each ofthe plurality of LED chains. The control module can comprise aninterface coupled to receive an intensity value from, for example, aremote controller that is remotely placed relative to the illuminationdevice, and specifically the control module that comprises a controllerwithin the illumination device. A storage medium can include anon-linear first mapping of the intensity value received from the remotecontroller to the brightness value sent to the LED chains. The storagemedium can also include a second mapping of the color temperature as afunction of the time of day. The control module can further comprise thecontroller within the illumination device, the controller is coupled toreceive a change in the intensity value from the interface and to fetchthe first and second mappings from the storage medium to produce achange in the color temperature during a first time of day relative to asecond time of day. According to one embodiment, the change in intensityvalue can decrease the color temperature during the daytime, as part ofa dimming function. Depending on the task, however, the change inintensity value can increase the color temperature if reverse dimming isneeded during, for example cloudy days when a higher temperature isneeded for a reading task, for example. Also, intensity value can beincreased if the current emulated output is nighttime and a user wishesto increase color temperature if he/she awakens from the bed, forexample.

User movement of the trigger on the remote controller correspondinglychanges the intensity value sent to the control module of eachillumination device within a group of illumination devices within, forexample, a room of a structure. As intensity is increased or decreased,task lighting can be manually controlled on a room-by-room basis.Moreover, the manual override applied on a room-by-room basis overridesthe automatic changes in color temperature output also applied on aroom-by-room basis. For example, actuation of a single trigger on aremote controller manually overrides an entire group of illuminationdevice automatic changes in color temperature output using an improveddiscovery and acknowledge process for group casting hereof. The changein intensity can correspond to either a fixed or variable change inbrightness applied to the LED chains. The fixed change in brightness canproduce a greater change in color temperature output from the LED chainsduring the first time of day than during the second time of day, whereasa variable change in brightness can produce an equal change in colortemperature output from the LED chains during the first time of day asthat of the second time of day. According to the first embodiment, thecolor temperature can change more so during a first time of day thanduring a second time of day even though the brightness output from theLED chains stays constant throughout the day but has changed the sameamount throughout the day or, according to the second embodiment, thecolor temperature can change the same amount during a first time of dayas that of a second time of day even though the brightness output fromthe LED chains changes throughout the day but has changed the sameamount.

Each of the plurality of LED chains can produce a spectral wavelengthrange that is different from the other of the LED chains. The drivercurrent to each of the plurality of LED chains is applied as a ratioamong the plurality of LED chains that automatically changes as afunction of the time of day. It is not until the interface that receivesan intensity value will the dynamic and automatic change functionalityterminate. The interface that is coupled to receive the intensity valueis one that receives during a lighting task, either dimming orreverse-dimming, for example, the manual override trigger from a uservia a remote controller, to temporarily stop the dynamic and automaticchanges in color temperatures as a function of the time of day.Alternatively, the dynamic and automatic changes in color temperaturescan continue yet at a dimmed, or reverse-dimmed level. For example, whenthe next time of day signal from a timer invokes the next colortemperature within the automatically changing color temperature show,the resulting color temperature can be greater than or less than whatwould normally be produced from the show. The manual override occurswhen a user actuates a button or a slider on either the remotecontroller, or on an AC mains coupled dimmer that comprises a triac.Actuation of the trigger on the remote controller or triac, for example,can cause the button or slider position to be sent as an intensity valueoutput from the remote controller or dimmer into the interface. Themanual dimming override will cause a change in the brightness outputfrom the plurality of LED chains. The manual dimming override andresulting change in brightness output will affect the LED output colortemperatures differently depending upon the time of day in which theuser actuates the trigger (e.g., button or slider).

If the color temperatures output from the LED chains dynamically andautomatically change from, for example, 2300 Kelvin to 6000 Kelvin fromsunrise to noon, for example, a manual task lighting override can occurby dimming the brightness output. The manual dimming of brightness inthe morning will have a greater effect in lowering the color temperaturethan if the brightness dimming were to occur at, for example, noontime.Even though the degree of brightness dimming is the same, the loweringof color temperatures via task dimming is advantageously greater in themorning than during noon. This benefit is key in that a user within thestructure would prefer to keep the higher color temperatures associatedwith noontime when he or she performs dimming for a task to be performedwithin that room of a structure. Nonetheless, a user would also preferto achieve a greater reduction in color temperatures during, forexample, the morning or evening hours since, during those hours, thecolor temperatures are already approaching the warm white colortemperature spectrum and further dimming for a task would notdeleteriously effect the users perception of the daylight emulation ofthe outdoor sunlight that is already at the lower color temperaturelocus. Historically, incandescent lights, which users are accustomed toare about 2700 K and will drop to as low as 1500 K when dimmed. Yet,high color temperature illumination devices, such as fluorescent or LEDillumination devices do not significantly change color temperature whendimmed. Thus, the purpose hereof for LED dimming more in the morning andevenings is generally contrary to conventional LED lighting operation,yet is desirably achieved through the present manual override that willalso maintain the conventionally desired less LED dimming when highercolor temperatures are implemented.

According to one embodiment, therefore, it is preferred that the drivecurrent to each of the plurality of LED chains automatically change as afunction of the time of day to change the color temperature output fromthe LEDs so as to emulate the natural daytime light of the sun from sunup to sun down. According to a further embodiment, although the drivecurrent to each of the plurality of LED chains automatically changesdepending on a timer output that correlates to the position of the sun,the interface allows for either a wire or wireless communication from atimer within a remote controller that is remote from the illuminationdevice. The remote controller that is remote from the illuminationdevice also allows for a trigger for a user to actuate the trigger andchange in the intensity value sent to the interface. The dimming orreverse-dimming trigger button slider can be configured on the remotecontroller or a triac-based dimmer remote from the illumination deviceand coupled to AC mains. That actuation not only changes the intensityvalue but correspondingly changes the brightness the same amount acrossall LEDs within one or more groups of illumination devices controlled bythe trigger button. Yet, depending on the time of day, that change inbrightness effectuated by the change in intensity value preferably has agreater effect when the LEDs would normally produce a lower colortemperature than when they produce a higher color temperature. Thebenefit of the differing effects on color temperature, albeit the samechange in brightness, is rooted in the human perception of emulatedsunlight with, as stated above, the motivation for a user retaining ahigher color temperature during peak sunlight hours than non-peak hourswhen a user would desire lower color temperatures during the override,manual dimming adjustment. That adjustment occurring whenever a userdesires a dimming from a higher brightness to a lower brightness forperforming certain tasks, yet maintaining a higher color temperatureduring peak sunlight hours and more substantially reducing the colortemperatures during non-peak sunlight hours.

According to yet another embodiment, an illumination system is provided.The illumination system can comprise a plurality of LEDs configured toproduce a plurality of color temperatures along the black body curve. Atimer can also be provided for producing a plurality of times of daycomprising a first time of day and a second time of day. A drivercircuit can be coupled between the timer and the plurality of LEDs toreceive the plurality of times of day and assign a drive current to theplurality of LEDs to produce a first color temperature during a firsttime of day and a second color temperature during a second time of day.The driver circuit automatically and dynamically produces the firstcolor temperature and the second color temperature depending on when thetimer produces the first time of day and the second time of day signals.However, the dynamic and automatic production of the first colortemperature and second color temperature can be overridden by useractuation upon the trigger. A control module, and specifically aninterface coupled to the control module, can receive the intensity valuefrom the remote controller or dimmer and can send a correspondingbrightness value to each of the plurality of LEDs. The brightness valueis determined based on a non-linear first mapping of the intensity valueto the brightness value. That non-linear first mapping can be stored ina storage medium, along with the second mapping of the color temperatureas a function of the time of day. The storage medium, and specificallythe first and second mappings are used by a controller. When thecontroller receives a change in the intensity value from the remotecontroller or dimmer, the controller fetches the first and secondmappings from the storage medium and can produce a greater change incolor temperature during the first time of day than during a second timeof day, even though the brightness change resulting from the intensityvalue change is equal at both the first time of day and the second timeof day.

The timer within, for example, the remote controller is preferably anymodule, circuit or system that has a clock. The clock preferably changesdepending on position of the earth relative to the structure in whichthe timer is placed. The clock can be coupled to any synchronizingsystem, such as the crystal oscillator, or can receive periodic feedsfrom, for example, a satellite or over the Internet. Moreover, the clockcan be preferably reset based on latitude and longitudinal coordinatesof where the timer resides, as well as the particular time zone wherethe time resides. The timer produces the plurality of times of day atwhatever interval is desired by the user, such as every minute, hour, orseveral hours. The plurality of times of day can therefore includedaylight hours, beginning with, for example, 6 a.m., 7 a.m., 8 a.m.,etc. if the regular timed intervals are set to be hourly. Alternatively,the timer produces time of day signals only on select times, such assunrise, an hour after sunrise, an hour before sunset and/or sunset. Inthe latter example, the timer can produce in relatively short intervals(e.g., 10 minute intervals) over a fixed period of time (e.g., one hour)to cause a smoothing or “fading” effect each time the color temperaturechanges after sunrise and before sunset. To an observer, the colortemperature would therefore change over a series of increasing ordecreasing steps or linearly to increase or decrease the automatic colortemperature changing show.

Like the timer that is preferably configured in the remote controller(i.e., physical keypad or portable computing device wired or wirelesslycoupled to the group or groups of illumination devices), the AC-mainscoupled dimmer is also configured remote from the illumination devices.The remote controller or dimmer manually changes the brightness valuenon-linearly and, depending upon the time of day, changes the colortemperature differing amounts. A change of the intensity value outputfrom the dimmer changes the brightness value equally among the pluralityof LEDs yet, depending upon the time of day, changes the colortemperature an equal or a differing amount. For example, the dimmer cancomprise a trigger that, when actuated by the user, changes the colortemperature more before 10 a.m. and after 4 p.m. than between 10 a.m.and 4 p.m. Also, when actuated by a user, movement of the trigger on thedimmer can register a change in the corresponding intensity value and,correspondingly, the brightness value. The color temperature preferablydecreases more before 10 a.m. and after 4 p.m. than between 10 a.m. and4 p.m. More preferably, color temperature decreases more an hour or twoafter sunrise and an hour or two before sunset than in the interimbetween sunrise and sunset. Those times are the local times relative tothe geographic location of the structure containing the illuminationdevices.

According to yet another preferred embodiment, the plurality of LEDs cancomprise a first plurality of LEDs. A second plurality of LEDs can begrouped with the first plurality of LEDs within a room of a structure.Accordingly, two or more LED-based illumination devices can be groupedtogether within a room of a structure. Those illumination devices can bea group of downlight PAR illumination devices mounted in a ceiling,and/or one or more A20 illumination devices or A19 illumination devicesplaced in lamps on nightstands, for example. Regardless of the type ofillumination device, or its functionality, the illumination devices canbe grouped with each other for control purposes. Typically, however, agroup of the illumination devices are generally configured in geographicproximity to one another within one room of a structure, for example.Therefore, preferably according to some embodiments, the groupedplurality of illumination devices can be configured to produce the samecolor temperature among all of the illumination devices within thatgroup. The color temperature among the grouped plurality of illuminationdevices is set by datasets stored as content within each of the groupedplurality of illumination devices. That content of datasets isconfigured and thereafter stored in the grouped illumination devicesusing the remote controller, for example. The remote controller cantherefore not only discover all illumination devices within a structureand thereafter to group certain sets of illumination devices, butfurthermore can assign content of datasets defining the chromaticity andbrightness values of each illumination device with the group.Thereafter, when a time-based show is invoked by the timer, such as theautomatic fading in of color temperature change, periodic times of daysignals are sent to specific the grouped set of illumination devices.This causes all of the illumination devices within that group to undergoan automatic change in color temperature, and possibly also brightnessoutput, throughout the day. Accordingly, the preferred method includesautomatically changing the color temperature among the grouped pluralityof illumination devices based on periodic, differing times of daysignals sent from a timer remote from the grouped plurality ofillumination devices to emulate changing natural light produced by thesun.

The preferred method of illumination further comprises manually dimmingthe brightness among the grouped plurality of illumination devices,resulting in the color temperature changing as a function of a currenttime of day signal sent from the timer. Specifically, if manual dimmingoccurs at a first time of day (i.e., at the current time of day signalfor the first time of day), the color temperature may change more sothan if the manual dimming occurred during a second time of day (i.e.,at the current time of day signal for the second time of day). Themanual dimming can maintain its override status of either terminatingthe automatically changing the color temperatures or anincrease/decrease in the automatically changing color temperatures untila timeout timer elapses, a pre-determined time of day signalsubsequently occurs, or possibly the next pre-determined time of daysignal that subsequently occurs. The override status can be maintainedindefinitely or, for a specific, pre-determined time amount. Moreover,the manual override, and specifically the change in intensity in dimmingor reverse-dimming levels can gradually occur based on a plurality ofsteps, linearly, exponentially or any user-desired dimming or reversedimming gradient over a fixed amount of time or a changing amount oftime to gradually fade the automatically changing color temperaturechanges. The details of which, including the details of each of theabove embodiments is further described herein below.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects and advantages of the invention will become apparent uponreading the following detailed description and upon reference to theaccompanying drawings.

FIG. 1 is a graph of the 1931 CIE chromaticity diagram illustrating theblackbody curve of color perception or color temperatures, and the gamutof spectral wavelengths achievable by the illumination device comprisinga plurality of LEDs of different color;

FIG. 2 is an exemplary color temperature space along the blackbody curveshowing four boundaries of illumination from the plurality of LEDs;

FIG. 3 depicts an angular relationship between a structure containingthe illumination device and the sun, including changes in path lengthtraveled by daytime sunlight throughout the day;

FIG. 4 is a graph of the relationship between dominant wavelengthsthroughout the daytime depending on the path length of the sun;

FIG. 5 depicts an array of different colored LEDs within an illuminationdevice, where each of the different colored LEDs can be configuredwithin a chain of similarly colored LEDs;

FIG. 6 is an exemplary plan diagram of a structure containing aplurality of illumination devices arranged in one or more groups withinone or more rooms of a structure, with corresponding remote controllersalso placed throughout one or more rooms within the structure;

FIG. 7 is an exemplary block diagram of the illumination devicecomprising a power supply converter, LED driver circuit, control circuitcontroller and a plurality of different colored LED chains;

FIG. 8 is an exemplary block diagram of the LED driver circuit that maybe included within the illumination device of FIG. 7;

FIG. 9 is an exemplary GUI of a remote controller remote from theillumination devices, further illustrating the commissioning of physicalillumination devices to groups possibly associated with a particulararea or room within the structure;

FIG. 10a is an exemplary GUI of the controller shown in FIG. 7, furtherillustrating the assignment of groups of illumination devices to, forexample, a keypad button;

FIG. 10b is an exemplary GUI of the controller shown in FIG. 7, furtherillustrating the assignment of a scene or scene which changes as afunction or time (i.e., show) to one or more groups previously assignedto, for example, a keypad button;

FIG. 10c is an exemplary GUI of the controller shown in FIG. 7, furtherillustrating the assignment of color and brightness to each scene andassignment of a time for invoking each scene to formulate a show;

FIG. 11 is a graph of the spectral sensitivity of brightness atdifferent color wavelengths;

FIG. 12 is a graph of brightness at different intensities, such as poweror current, supplied to the illumination device;

FIGS. 13a and 13b are graphs of different color temperatures appearingat different times of the day, and the differing effect of brightnesschanges on those color depending on when the brightness is changed;

FIG. 14 is a block diagram of content (or datasets) stored in thestorage medium of the illumination device and the time message sent fromcontroller to address a different dataset depending on the status of thereal time clock within the controller, and to automatically change thecolor output from the illumination device depending on the status ormanually change the color output from the illumination device if adifferent dataset is addressed;

FIG. 15 is graph of color temperature changing as a function of bothtime of day and brightness;

FIG. 16 is another graph of color temperature changing as a function ofboth time of day and brightness; and

FIG. 17 is a block diagram of intensity forwarded to a brightness dimcurve and brightness forwarded to a color emulation curve to generate atarget color temperature whenever the daytime emulation show, forexample, is manually changed.

While the invention is susceptible to various modifications andalternative forms, specific embodiments thereof are shown by way ofexample in the drawings and will herein be described in detail. Itshould be understood, however, that the drawings and detaileddescription thereto are not intended to limit the invention to theparticular form disclosed, but on the contrary, the intention is tocover all modifications, equivalents and alternatives falling within thespirit and scope of the present invention as defined by the appendedclaims.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Among the various advantages of LED-based illumination devices is thatLEDs offer distinct opportunities of being able to integrate artificiallight with natural light, and to provide helpful and healthful lightingthrough dynamic lighting mechanisms. One particular niche of LED-basedillumination devices is in the generation of artificial sunlight for avariety of reasons, especially for treating human ailments such ascircadian rhythm disorders, seasonal affection disorders, shift workcondition disorders, etc. The mechanism by which many conventionalLED-based illumination devices replicate or “emulate” natural sunlightconditions is through use of sensors. The sensors can detect thesunlight conditions within a structure interior to that structure, andcreate artificial lighting from the illumination device that attempts toreplicate the natural sunlight conditions or the emulated sunlightoutside the structure. Unfortunately, sensors have limitations both intechnology and the location where those sensors are located. The sensorstherefore do not always accurately detect the exterior sunlightconditions, and the outdoor natural sunlight conditions sometimes cannotbe properly emulated.

Accordingly, another more preferred alternative mechanism is to keeptrack of the time of day and send a plurality of times of day valuesfrom a timer to the LED-based illumination devices. Instead of using asensor, with various flaws associated with that sensor, a timer is usedand the emulated sunlight changes based on the times of day values ordata sent from the timer. Use of timers and time of day values provesbeneficial if the circadian show is to be tailored differently dependingon the room in which sunlight is being emulated. Sensors cannot tailoremulation depending on the room, but instead sense and provide emulationconsistently throughout the structure. Grouping of illumination deviceson a room-by-room basis and controlling each room separately usingdifferent remote controllers and associated timers with different timeof day values is therefore indigenous to timers and not sensors—an addedbenefit of not using sensors to control sunlight emulation. Of course,there are acceptable limits in using a timer versus a sensor. A timerchanges the time of day value sent to the illumination device to updatethe illumination device output at periodic intervals throughout the day,without regard to whether the exterior conditions change outside thenormal conditions that would occur during that time of day. For example,a timer in and of itself cannot detect cloudy exterior conditions,partly cloudy, overcast, foggy, or rainy conditions unless that timerwere coupled to a sensor, and that sensor is preferably placed outsidethe structure and communicatively linked to the timer. Accordingly, thetimer, and the communication of a plurality of times of day values, ordata, sent from the timer of a remote controller illumination deviceshereof is limited to the normal sunlight conditions expected during thevarious times of day. Use of a timer to emulate sunlight is bound towhat is statistically normal sunlight conditions in some cases, but canbe tailored depending on the room orientation to sunlight conditions.The benefit of selectively tailoring emulation depending on the group ofillumination devices being controlled and the room orientationcontaining those devices outweighs any benefit of using sensors insteadof timers. The individual control and tailoring on a room-by-room basisamong groups of illumination devices proves to be a more superiorcontrol mechanism than sensors in the majority of days throughout theyear. Any deviation from what the timer determines to be normal time ofday sunlight emulations, and what is actually occurring outside is anacceptable deviation and does not distract from the sunlight emulationperformed by the timer, and the benefits of tailoring the timer controlamong rooms within the structure. Use of only a timer without a sensoralso proves adequate simply from the ease of use by which a timeroperates rather than the inaccurate and oftentimes flawed sensorreadings used to sense out-of-normal outside sunlight conditions. If theemulation show being produced, however, is not acceptable to a user, theuser can always manually change the color temperature output at anytime, as described below.

According to one embodiment, it is preferred that the sunlightconditions are emulated by use of a timer that manipulates and updatesemulation from illumination devices based on calendar day and time ofday, and that functionality is performed automatically and dynamicallythroughout the day. The automatic emulation occurs as a dynamicallychanging show that continues automatically without user intervention,and specifically continues to change the color temperature output inresponse to the illumination devices receiving the time of day signalssent from the timer. Automatic emulation and the automatically changingcolor temperature occurs without the user actuating a trigger, thatfunctionally is reserved for the manual override and not the automaticshow. Thereafter, depending on tasks needed by a user or if the userwishes to manually change the emulation to be more accurate as to whatis occurring outside the structure, the user can manually change thecolor temperature output from an illumination device or a specific groupof illumination devices either in a single step in response to useractuation or gradually in a smoothing plurality of steps or linearly asa function of time. The same reversion in a smoothing plurality of stepsor linearly as a function of time can occur back to the automaticallyand dynamically changing emulation output after the task is completed,or after a user actuates a dimmer back to its previous trigger positionor after the next time of day sunlight emulation change occurs, or theone thereafter.

FIG. 3 illustrates in further detail the daytime locus and the spectralcharacteristics that resemble sunlight shown in FIGS. 1 and 2 resultingfrom the positional change of sun 16 relative to, for example, astructure 18 bearing one or more illumination devices. As shown in FIG.3, the angular relationship between sun 16 and structure 18 changesthroughout the day, where the angular relationship is often referred toas the zenith angle, Ø_(z). As the sun 16 moves from an overheadposition to a position nearly horizontal with the earth's surface 20,the path length (PL) increases from PL₁ to PL₄. Importantly, thespectral distribution of sunlight, specifically the spectral radiance ofsunlight changes with PL. As shown in FIG. 4, shorter wavelengths can bemore sensitive and produce greater spectral radiance at shorter PLs thando longer wavelengths. A combination of FIGS. 3 and 4 illustrate that assun 16 is directly over structure 18, the shorter path length (PL₁)produces a greater amount of lower wavelength chromaticity spectrum, andas sun 16 approaches the horizon, the longer path length (PL₄) shows apredominance of longer wavelength spectral radiance. At PL₁, the naturalsunlight condition is typically more of a cool white or natural sunlightcolor temperature having a preponderance of blue versus red and yellow.Conversely, as the path length increases to PL₄, the color temperatureapproaches more of the warm white associated with incandescent lightingor halogen lighting, with a preponderance of red and yellow versus blue.In order to emulate the changes in natural sunlight conditions within anartificial lighting system, such as the present illumination device, ordevices, the illumination device must change its color temperatureoutput throughout the day based on, for example, the changing pathlengths (PL_(s)).

FIG. 5 partially illustrates a “white” LED illumination device 24.Illumination device formulates the white illumination by comprising, forexample, a plurality of white LED semiconductor devices 26, a pluralityof yellow-green semiconductor devices 28, a plurality of red LEDsemiconductor devices 30 and, if illumination device 24 is an RGB-basedillumination device, a blue LED semiconductor device 32. The red, green,blue, and white semiconductor devices are each defined in a particularchromaticity region of the chromaticity space that includes a targetchromaticity region of combined light emitted by the red, green, blueand white light emitters. The RGB system can form white light of aparticular color temperature depending upon the mixing of the variousred, green, blue chromaticity regions, for example. The red, green,blue, and white semiconductor devices are made from a variety of organicor inorganic semiconductor materials, each producing a differentchromaticity or wavelength output. Certain of the red, green, blue orwhite semiconductor devices can be encapsulated with a coating to alsoproduce the desired chromaticity wavelength output. For example, thewhite LED semiconductor device can comprise phosphor-coated blueemitting LED semiconductor device. Moreover, by independentlyattenuating each of the three, or four RGB or RGBW LED (or LED chains)the illumination device 24 is capable of producing a wide color gamut,with a color temperature along the black body curve and, according tothe desired output along a daytime locus.

FIG. 6 illustrates an example of a structure 36 containing a pluralityof illumination devices 38. Illumination devices 38 are sometimesinterchangeably referred to simply as lamps, fixtures, or luminaries. Aresidence 36 may have numerous rooms, such as bedrooms, living rooms,etc. Preferably each illumination device comprises at least one LED, andmore preferably, several LED chains, where each chain can produce acorresponding color within a chromaticity region. Illumination devices38 can include PAR illumination devices shown as downlights 38 a within,for example, a living room, and other PAR illumination devices 38 c asdownlights within, for example, a bedroom. For example, the living roomcan have four downlights labeled 38 a, whereas the bedroom can havethree downlights labeled 38 c. Next to the couch within, for example theliving room, are tables on which, for example, A20 illumination devices38 b are configured.

Preferably each illumination device includes a communication interfacefor a first communication protocol, that communication protocol being awireless communication protocol used by all of the illumination devices38 within, for example, residence 36. A popular first communicationprotocol can be WPAN using IEEE 802.15.4 and/or any protocol basedthereon, like ZigBee. The illumination devices can therefore wirelesslycommunicate with each other, if desired. In addition to the illuminationdevices being wirelessly interconnected, remote controllers can also beinterconnected, either wirelessly or wired. The remote controllers shownin FIG. 6 can be physical keypads 40 a and 40 b associated with, forexample, the living room and bedroom, respectively. As will be notedlater, the physical keypads can be replaced by virtual keypads, andassigned to, for example, a mobile phone and specifically the GUI shownon the mobile phone or mobile computer. The remote controllers cantherefore be a physical keypad connected via a wire or wirelessly to thegroup or groups of physical illumination devices controlled by thephysical keypad, or the remote controllers can be a computer-basedportable device connected wirelessly to the group or groups ofillumination devices controlled by a virtual keypad shown on a GUI ofthe wireless portable device. The virtual keypad shown on the GUI of themobile device can appear identical to the physical keypads, with virtualtriggers (i.e., buttons, sliders, etc) similar to the actual triggers onthe physical keypads. The physical keypads can communicate eitherthrough a wire, or wirelessly, to their corresponding illuminationdevices, whereas the virtual keypad shown on a GUI of a mobile devicecan communicate using a wireless communication protocol, such as WPAN,or ZigBee. Also, as opposed to the first communication protocol in whichthe physical lamp in the illumination devices 38 and the physicalkeypads 40 communicate, a second communication protocol is linked to thefirst communication protocol via a bridge 42 that can be placed inproximity to the residence and the residence 36 can allow a secondcommunication protocol such as Ethernet, WiFi, Bluetooth, etc. tocommunicate from, for example, a mobile phone to the illuminationdevices 38.

FIG. 7 illustrates an exemplary block diagram of illumination device 38,according to one embodiment of the invention. The illumination deviceillustrated in FIG. 7 provides one example of the hardware and/orsoftware that may be used to implement a method of emulating naturalsunlight both dynamically and automatically, and thereafter manuallyoverriding that emulation when one or more lighting tasks are needed.The manual override may be needed to either perform a temporary task orto emulate more accurately the current outside sunlight conditions—e.g.,change from a cloudless sunny outside sunlight condition to a cloudy orrainy condition.

Physical illumination device 38 comprises a plurality of emission LEDs40, and in this example comprises four chains of any number of seriallyconnected LEDs. Each chain may have two to four LEDs of the same color,which are coupled in series and configured to receive the same drivecurrent. In one example, the emission LEDs 40 may include a chain of redLEDs, a chain of green LEDs, a chain of blue LEDs, and a chain of whiteor yellow LEDs. However, the preferred embodiments are not limited toany particular number of LED chains, any particular number of LEDswithin each chain, or any particular color or combination of the LEDcolors. In some embodiments, the emission LEDs 40 may be mounted on asubstrate and encapsulated within a primary optic structure of anemitter module, possibly along with one or more photodetectors.

In addition to emission LEDs 40, illumination device 38 includes varioushardware and software components for powering the illumination deviceand controlling the light output from the one or more emitter modules.In the embodiment shown in FIG. 7, illumination device 38 is connectedto AC mains 42 and includes an AC/DC converter 44 for converting the ACmains voltage (e.g., 120V or 240V) to a DC voltage (V_(DC)). The DCvoltage (e.g., 15V) is supplied to LED driver circuits 46 to produce thedrive currents, which are supplied to the emission LEDs 40 for producingillumination. In the embodiment of FIG. 7, a DC/DC converter 48 isincluded for converting the DC voltage (V_(DC)) to a lower voltage V_(L)(e.g., 3.3V), which is used to power the lower voltage circuitry of theillumination device, such as the phase-locked loop (PLL) 50, interface52, and control circuitry 54. In other embodiments, illumination device38 may be powered by DC voltage source (e.g., a battery), instead of ACmains 42. In such embodiments, the illumination device may be coupled tothe DC voltage source and may or may not include a DC/DC converter inplace of the AC/DC converter 44. Additional timing circuitry may beneeded to provide timing and synchronization signals to the controllingdriver circuits.

In the illustrated embodiment, PLL 50 is included within illuminationdevice 38 for providing timing and synchronization signals. PLL 50 canlock onto the AC mains frequency and can produce a high speed clock(CLK) signal and a synchronization signal (SYNC). The CLK signalprovides timing signals for control circuit 54 and LED driver circuits46. In one example, the CLK signal frequency is in the tens of MHz range(e.g., 23 MHz), and is precisely synchronized to the AC mains frequencyand phase. The SYNC signal is used by the control circuit 54 to createthe timing signals used to control the LED driver circuits 46. In oneexample, the SYNC signal frequency is equal to the AC mains frequency(e.g., 50 or 60 HZ) and also has a precise phase alignment with the ACmains.

In some embodiments, interface 52 may be included within illuminationdevice 38 for receiving datasets, or content, from an externalcalibration tool during manufacturing of the device, or duringprovisioning or commissioning of the illumination device, or group ofillumination devices. The datasets or content received via interface 52may be stored in a mapping table within storage medium 56 of controlcircuit 54, for example. Examples of dataset or content that may bereceived via interface 52 include, but are not limited to, the luminousflux (i.e., brightness values), intensity, wavelength, chromaticity ofthe light emitted by each LED chain (i.e., when mixed forms the colortemperature) and, more specifically, as will be described in more detailbelow, (a) a mapping of brightness values to intensity values, and (b)color temperature to both brightness values and times of day values.

Interface 52 is not limited to receiving datasets or content duringprovisioning or commissioning of the illumination device or group ofillumination devices. Interface 54 can also be used to receive commandsfrom, for example, a remote controller 64. Commands can also be sentfrom dimmer 52 to control circuit (controller) 54. Dimmer 62 can becoupled to the AC mains, as shown, similar to a triac, to allow manualoperation of the dimmer by a user. The triac of dimmer 62 changes thephase cut rms voltage on the AC mains, and forward the correspondingintensity value derived therefrom into the illumination device. Byactuating a trigger button or slider on the remote controller 64 ordimmer 62, a dimming or reverse-dimming command in the form of anintensity value can be sent to driver circuits 46. As opposed toactuating a trigger on dimmer 52, a user can actuate a trigger (i.e.,button or slider) on a user interface of a remote controller, such as aphysical keypad or on a graphical user interface of a portable computersuch as a smart phone or laptop to allow the dimming or reverse-dimmingcommand to be sent from remote controller 64 via interface 52, eitheracross a wire or wirelessly. A reduction in intensity value as a resultof dimming (or an increase in intensity value as a result ofreverse-dimming), either via dimmer 62 or remote controller 64, willcause a decrease/increase in brightness due to the mapping table storedin medium 56 and fetched by the control circuit controller 54. Forinstance, commands may be communicated to illumination device 38 viadimmer 62 or remote controller 64 and interface 52 to turn theillumination device on/off, to control the brightness level and, asdescribed below to manually and temporarily override the colortemperature sunlight emulation show (daytime or nighttime) whenperforming a task or when performing a more accurate color temperatureemulation to the actual sunlight condition—e.g., cloudy, rainy orovercast outdoor condition.

Interface 52 may comprise a wireless interface that is configured tooperate according to ZigBee, WiFi, Bluetooth, or any other proprietaryor standard wireless data communication protocol. In other embodiments,interface 52 could communicate optically using infrared (IR) light orvisible light. Alternatively, interface 52 may comprise a wiredinterface to a wired physical keypad of remote controller 64, which isused to communicate information, data and/or commands over the AC mains12 or a dedicated conductor, or a set of conductors. In anotheralternative embodiment, interface 52 may additionally or alternativelycomprise an interface to a remote controller 64 wirelessly connectedlaptop or portable computer having a GUI, or to a physical keypad havinga user interface or GUI or at least one trigger (e.g., button, slider,knob or switch) for controlling the illumination device 38. A skilledartisan would recognize that a number of different interfaces may beincluded within the illumination device for communicating information,commands and control signals.

According to one preferred embodiment, interface 52 is coupled forreceiving control signals from a remote controller 64 and specificallyfrom a user actuating a trigger on the remote controller 64 for alteringan automatically changing illumination show among one or more groups ofillumination device 38. As per the automatically changing illuminationshow, the remote controller 64 can include a timer that sends aplurality of times of day signals to the control circuit controller 54via the interface 52. For example, if the remote controller 64 comprisesa physical keypad 40 having a real time clock therein, the real timeclock, depending on the calendar day and time of day, periodically sendsa time of day signal from among a plurality of times of day signals. Thetime of day signal is unique to the calendar day and time of dayrecorded and output by the timer. If the time of day signals are sent,for example, every hour, only the specific time of day signal for thatcurrent hour is sent from among the plurality of times of day signals,each corresponding to a different hour.

Using the timing signals received from PLL 50 and the control signalsfrom interface 52 (e.g., a periodic set of time of day signals sent froma remote timer to create a show having a change in daylight emulation asa function of time of day, and a dimmer to perform a dim function tochange intensity values a desired brightness level), control circuitcontroller 54 calculates, based on brightness and color temperaturemappings as a function of brightness and time of day stored in medium56, and produces values indicating a desired drive current to besupplied to each of the LED chains 40. This information may becommunicated from control circuit controller 54 to LED driver circuits40 over a serial bus conforming to a standard, such as SPI or I²C, forexample. In addition, control circuit 54 may provide a latching signalthat instructs the LED driver circuits 46 to simultaneously change thedrive currents supplied to each of the LED chains 40 to preventbrightness and color artifacts.

In some embodiments, controller 54 may be configured for determining therespective drive currents needed to achieve a desired luminous fluxand/or a desired chromaticity for the illumination device in accordancewith one or more of the compensation methods described in U.S. patentapplication Ser. No. 14/314,530 published on Dec. 31, 2015 as U.S.Publication No. 2015/0382422 A1; Ser. No. 14/314,580 issued on Jul. 12,2016 as U.S. Pat. No. 9,392,663; and Ser. No. 14/471,081 published onMar. 3, 2016 as U.S. Publication No. 2016/0066384 A1, which are commonlyassigned and incorporated herein in their entirety. In a preferredembodiment, control circuit controller 54 may be further configured foradjusting the drive currents supplied to the emission LEDs 40, so as notto exceed a maximum safe current level or a maximum safe power levelattributed to one or more power converters of the illumination device 38at a present operating temperature as determined by temperature sensor58.

As shown in FIG. 7, temperature sensor 58 may be included within theillumination device 38 for measuring a present operating temperature ofthe illumination device. In some embodiments, temperature sensor 58 maybe a thermistor, which is thermally coupled to a circuit board or chipcomprising one or more of the components shown in FIG. 7. For example,temperature sensor 58 may be coupled to a circuit board comprising AC/DCconverter 44, DC/DC converter 48, PLL 50 and interface 52. In anotherexample, temperature sensor 58 may be thermally coupled to the chipcomprising LED driver circuits 46 and emission LED chains 40. In otherembodiments, temperature sensor 58 may be an LED, which is used as botha temperature sensor and an optical sensor to measure ambient lightconditions or output characteristics of LED chains 40. The temperaturemeasured by the sensor 58 is supplied to the controller 54 for adjustingthe drive currents.

In some embodiments, control circuit controller 54 may determine therespective drive currents by executing program instructions storedwithin storage medium 56. In one embodiment, the storage medium 56 thatstores the first and second mappings may be a non-volatile memory, andmay be configured for storing the program instructions along with atable of calibration values, as described for example in U.S. patentapplication Ser. No. 14/314,451 published on Dec. 31, 2015 as U.S.Publication No. 2015/0377699 A1, and Ser. No. 14/471,057 issued on Dec.31, 2015 as U.S. Pat. No. 9,392,660, which are commonly assigned andincorporated herein in their entirety. Alternatively, control circuitcontroller 54 may include combinatorial logic for determining thedesired drive currents, and storage medium 56 may only be used forstoring the mapping tables of intensities as a function of brightnessvalues, and color temperatures as a function of brightness values andtimes of day.

In general, LED driver circuits 46 may include a number (N) of driverblocks 68 equal to the number of emission LED chains 40 included withinthe illumination device 38. In one exemplary embodiment, LED drivercircuits 46 comprise four driver blocks 68, each configured to produceillumination from a different one of the emission LED chains 40. In someembodiments, LED driver circuits 46 may comprise circuitry for measuringambient temperatures, measuring photodetector and/or emitter forwardvoltages and photocurrents, and adjusting the LED drive currents. Eachdriver block 68 receives data indicating a desired drive current fromcontrol circuit 54, along with a latching signal indicating when thedriver block 68 should change the drive current.

FIG. 8 is an exemplary block diagram of LED driver circuits 46,according to one embodiment of the invention. In the exemplaryembodiment of FIG. 8, LED driver circuits 46 include four driver blocks68, each block including a DC/DC converter 72, a current source 74, andan LC filter 76 for generating the operative drive currents (Idrv)supplied to a connected chain of emission LEDs 40 a to produceillumination, and the relatively small drive currents (Idrv) used toobtain emitter forward voltage (Vfe) measurements. In some embodiments,DC/DC converter 72 may convert the DC voltage (V_(DC)) into a pulsewidth modulated (PWM) voltage output (Vdr) when controller 80 drives the“Out_En” signal high. This PWM voltage signal (Vdr) is filtered by LCfilter 76 to produce a forward voltage on the anode of the connected LEDchain 40 a. The cathode of the LED chain is connected to current source74, which forces a fixed drive current (Idrv) equal to the valueprovided by the “Emitter Current” signal through LED chain 40 a when the“Led_On” signal is high. The “Vc” signal from current source 74 providesfeedback to the DC/DC converter 72 to output the proper duty cycle andminimize the voltage drop across current source 74.

As shown in FIG. 8, each driver block 30 may also include a differenceamplifier 78 for measuring the forward voltage (Vfe) drop across theconnected chain of emission LEDs 26 a. When measuring Vfe, DC/DCconverter 32 is turned off and current source 74 is configured fordrawing a relatively small drive current (e.g., about 1 mA) through theconnected chain of emission LEDs 40 a. The forward voltage drop (Vfe)produced across LED chain 40 a by that current is measured by thedifference amplifier 78, which produces a signal equal to Vfe. Theforward voltage (Vfe) is converted to a digital signal by analog todigital converter (ADC) 42 and supplied to controller 80. Secondcontroller 80 determines when to take forward voltage measurements andproduces the Out_En, Emitter Current and Led_On signals, which aresupplied to each of the driver blocks 68.

LED driver circuit 46 is not limited to the embodiment shown in FIG. 8.In some embodiments, each LED driver block 68 may include additionalcircuitry for measuring photocurrents, which are induced across one ormore of the emission LED chains 40, when these chains are configured fordetecting incident light (e.g., ambient light or light emitted fromother emission LEDs). In some embodiments, LED driver circuit 46 mayadditionally include one or more receiver blocks (not shown) formeasuring forward voltages and/or photocurrents induced across one ormore photodetectors, which may also be included within the emittermodule. In some embodiments, LED driver circuit 46 may include atemperature sensor for measuring a temperature of the driver circuitryand a multiplexer for multiplexing the emitter forward voltages (Vfe)and measured temperatures to the ADC 82. Exemplary embodiments of such adriver circuit are described in the previously mentioned co-pendingapplications.

DC/DC converter 48 and DC/DC converters 72 may include substantially anytype of DC/DC power converter including, but not limited to, buckconverters, boost converters, buck-boost converters, Ćuk converters,single-ended primary-inductor converters (SEPIC), or flyback converters.AC/DC converter 44 may likewise include substantially any type of AC/DCpower converter including, but not limited to, buck converters, boostconverters, buck-boost converters, Ćuk converters, single-endedprimary-inductor converters (SEPIC), or flyback converters. Each ofthese power converters generally comprise a number of inductors (ortransformers) for storing energy received from an input voltage source,a number of capacitors for supplying energy to a load, and a switch forcontrolling the energy transfer between the input voltage source and theload. The output voltage supplied to the load by the power converter maybe greater than or less than the input voltage source, depending on thetype of power converter used.

According to one preferred embodiment, AC/DC converter 44 comprises aflyback converter, while DC/DC converter 48 and DC/DC converters 72comprise buck converters. AC/DC converter 44 converts the AC mains power(e.g., 120V or 240V) to a substantially lower DC voltage V_(DC) (e.g.,15V), which is supplied to the buck converters 48/72. The buckconverters 48/72 step down the DC voltage output from the AC/DCconverter 44 to lower voltages, which are used to power the low voltagecircuitry and provide drive currents to the LED chains 40.

In some embodiments, the brightness level may be adjusted from thedimmer 62 or remote controller 64 substantially continuously between aminimum level (e.g., 0% brightness) and a maximum level (e.g., 100%brightness), or vice versa. The adjustment can be linear, but in mostcases due to the difference in slider adjustment on the dimmer andremote controller 64 in relation to the brightness output, theadjustment is non-linear and is more on a logarithmic scale as shown inand described in FIG. 12. Specifically, the movement of a triggerposition (movement of a slider, amount of time depressing a button, orwhether one or multiple buttons are depressed) translates to theintensity value. The position of the trigger position can correspond toan intensity value, but the trigger position/status or intensity valueis non-linear with respect to the brightness level. Thus, actuation ofthe trigger does not translate to exact “one-to-one” changes on of thebrightness level. A non-linear mapping is needed. By defining thebrightness level as a 16-bit variable scaling can be easilyaccomplished. In other embodiments, the brightness level may be adjustedbetween a limited number of predefined steps, wherein each stepcorresponds to a percent change in brightness (e.g., 0%, 25%, 50%, 75%or 100% maximum brightness) or a decibel change (e.g., +/−1 dB) in lumenoutput.

FIG. 9 illustrates an example in which actual physical illuminationdevices 38 are grouped based on their location and function. Themechanism for providing the grouping as well as the function of theillumination devices will be disclosed later when describing thegrouping mechanism as well as the scene/show assignment mechanism.However, as shown in FIG. 9, a location such as the bedroom can have agroup of illumination devices 38 and, associated with that group ofillumination devices 38, is a particular scene or show. Since each ofthe illumination devices 38 has one or more LEDs, the RGB of theplurality of LEDs can be tailored to any color, brightness or visualeffect desired by the user by setting a scene or a time-changing showwithin the grouped illumination devices.

FIG. 9 illustrates a plurality of physical illumination devicesappearing as virtual illumination devices on a graphical user interfaceof a remote controller 64, and specifically the GUI 85 of remotecontroller 64. The virtual illumination devices 39 correspond torespective actual illumination devices 38 within the structure. Inaddition to physical illumination devices 38 are physical keypads 40,shown in FIG. 6, spaced throughout the interior of a structure. Theillumination devices 38 can have any type of form factor including A20,PAR38, linear cove, wall washing lights, and track lights. The keypads40 can be mounted in a signal gang junction box and coupled to the ACmains. Moreover, virtual keypads appearing on the wireless or wiredremote controller 64 can eliminate the physical keypads 40. The virtualkeypads can exist on GUI applications on computers, and specificallymobile devices like a smartphone. The keypads, whether physical orvirtual, are typically described as a remote controller 64 if the remotecontroller consists of a wired physical keypad or a wireless mobiledevice having a GUI on which the virtual keypad is shown. In addition tothe network of physical illumination devices 38 and physical keypads 40,a remote controller 64 is used to control the communication to and fromthe network of physical illumination devices 38 and physical keypads 40.Remote controller 64 is essentially an execution unit that executes oninstructions and data to present a GUI the user can use to perform thegrouping and scene/show assignments described in FIGS. 10b and 10c .Control instructions are sent through a communication interface fromcontroller 64 to the network of illumination devices 38. Thecommunication interface for controller 64 simply communicates correctlyto the illumination devices and keypads using, for example, ZigBeecommunication protocol. Remote controller 64, can also communicatethrough a different protocol if a bridge or hub is needed to bridgebetween ZigBee protocol in which the illumination devices 38 communicateand the protocol used by remote controller 64. For example, a softwareapplication can operate on controller 64, possibly on either Apple orAndroid mobile devices to present the virtual keypad on controller 22. Ahub or bridge connects between WiFi and the wireless lamp network whichcan use ZigBee. If remote controller 64 communicates directly without anintermediate bridge or hub, then a dongle with a radio interface willallow the GUI of remote controller 64 to communicate directly with thenetwork of physical illumination devices 38 and physical keypads 40.

A typical installation in a structure will have physical keypads 40 anda variety of physical illumination devices 38 in every room. In somecases, some rooms may have multiple keypads controlling the sameillumination devices just like conventional two or three-way lightswitches, where a three-way switch uses two switches and a two-wayswitch uses one switch—on/off. The physical keypads 40 in each room thencontrol the color, brightness, spectrum, or visual effects in general.The keypads can control such effects either statically, or as a functionof time. A static control would simply be a user pushing a triggerbutton or slider on the physical keypad. The illumination devices 38 andphysical keypads 40 in a residence can also be controlled by a computerrunning an application with a radio-based dongle plugged into a USBport, or can be controlled by a mobile device, such as a smartphone alsorunning a software application. The dongle can communicate ZigBeemessages directly, whereas the bridge or hub converts between WiFi andthe ZigBee messages, for example.

After the physical illumination devices 38 and physical keypads 40 areinstalled in a structure, the physical illumination devices 38 andphysical keypads 40 must be discovered before the grouping and scenebuilding procedures. Thus, a first step when using, for example, acontroller with a dongle is to discover all the illumination devices andkeypads within range of that controller. The wireless network that theillumination devices 38 and keypads 40 use is preferably a mesh network,so illumination devices or keypads that are physically distant may stillbe in communication range of the controller through one or more hops.When a user instructs the controller to discover all devices, possiblythrough a command on the GUI of the controller, the dongle broadcasts amessage instructing all devices that receive the message either directlyor through any number of hops, to respond with their unique ID number,often times referred to as the MAC address. The unique MAC addresses ofeach of the illumination devices, as well as the keypads, are sent backto the remote controller 64. If the remote controller 64 is a personalcomputer or a phone having a screen, it displays on that screen a set ofGUI icons as virtual illumination devices representing the correspondingphysical illumination devices that have responded. The icons arereferred to as the virtual illumination devices since a need exists todistinguish between the illumination devices that appear on the GUI asvirtual illumination devices 39 and illumination devices that exist inthe residence, or physical illumination devices 38.

For example, as shown in FIG. 9, in an installation with six PARphysical illumination devices 38 in a structure, six virtualillumination device 39 icons will appear. The keypads will appear at alater step also as virtual keypad icons. An indication that all of theillumination devices have been discovered occurs when an acknowledgemessage is sent back from each of the illumination devices to the remotecontroller, which causes each physical lamp to turn blue, and eachphysical keypad to blink. Moreover, each of the discovered physicalillumination devices and physical keypads will appear as virtualillumination devices and virtual keypad icons on the GUI. If all of thephysical illumination devices do not turn blue or the keypads blink uponuser inspection by walking around the residence, not all acknowledgemessages have been returned and thus the missing acknowledge message ofthe unique MAC lamp address would indicate a non-blue physical lamp hasnot been discovered. Remedial measures would then need to be taken, asdescribed below. However, if all physical illumination devices turn blueon physical inspection, then the corresponding icons will appear and allof the physical illumination devices within the residence will appear asicons on the controller GUI.

After all of the physical illumination devices and physical keypads havebeen discovered, the next step is grouping. In the grouping procedure ormechanism, physical illumination devices that need to be controlledtogether are assigned a specific group address. As shown in FIG. 9,during the grouping mechanism group addresses are downloaded intostorage medium 56 of each illumination devices. Thereafter, during acontrol mechanism, a single button actuation of a physical keypad 40, oractuation of a group name assigned to a virtual button of a virtualkeypad will cause a control message to be sent from the controller toaddress via a single groupcast message all of the unique MAC addressesassociated with that unique group address to launch the contentassociated with that group of physical illumination devices viamicroprocessor fetch mechanism. Further descriptions of the groupaddressing, and storage of content within illumination devices 38 occurduring the grouping mechanism, as well as the scene builder or showbuilder mechanism.

There can be different types of remote controllers 64, and particularlythe communication protocols applied to the plurality of illuminationdevices 38. A remote controller 64 can simply include a dongle with aUSB interface and radio plugged into the USB port of a mobile device. Ifremote controller 64 is to communicate through a hub or bridge, thenremote controller 64 communicates using a different protocol then theprotocol at which the various illumination devices 38 communicate witheach other as well as the physical keypad 40.

During the discovery phase, for example, the broadcast discovery signalis sent from the remote controller 64 through the mesh network fromhop-to-hop, with an acknowledge-back from, for example, unique address,to unique address, to unique address, e.g., in hexadecimal. Thebroadcast discovery and acknowledge back forms a routing table with adestination address and next hop address for a particular lamp. Therouting table is stored in the memory of illumination device 38 alongwith what we will described later as the group address, as well as thecontent associated with that group address. The group address andcontent can have a group address of, for example F and C, respectfully,forming the groupcast table. An example of an illumination devicediscovery, groupcast table formulation and content (scene/show builder)for various groups of illumination devices and the flow diagram of eachprocedure is set forth in commonly assigned U.S. patent application Ser.No. 15/041,166, which is commonly assigned and herein incorporated byreference in its entirety.

The discovery process can be initiated by sending a discovery message.At least once, after the illumination devices 38 have been installed, anetwork configuration may be necessary. Such a network configuration maybe repeated, if necessary. Typically, the configuration or discoveryprocedure is only done once. However, if an illumination device isreplaced, the discovery process must be repeated any time theillumination system is modified. Thus, the discovery process can be doneif the network is modified or reconfigured, if illumination devices areadded or removed, or a modification of lighting scenes occurs. Whenconfiguring the network during the discovery phase, remote controller atfirst has no knowledge about the available illumination devices. Thestructure of the illumination system network is not predetermined byinstallation like the cabling structure of a wired network. Instead, itmay be determined by the plurality of physical conditions, like thedistance or shielding materials between neighbored illumination devices,walls, or other devices between the illumination devices, or even byelectromagnetic interference by electric appliances or other deviceswithin the structure 36.

To compute the network configuration, preferably a broadcast istriggered by the controller 64. The broadcast message is transmitted byaddressing the messages to a pre-defined broadcast address, to which allphysical devices (illumination devices and keypads) are listening. Forexample, the broadcast signal will be received first by those devicesthat are in close proximity to the controller. Those illuminationdevices can then forward the broadcast message to other illuminationdevices, which further forwards the message to even further distalillumination devices via one or more hops. To complete the networkconfiguration, it is necessary that the controller receives anacknowledge signal from each lamp, by which the lamp acknowledges thatit has received a broadcast message. The acknowledge signal ispreferably transmitted as a unicast or directed message back to thecontroller that sent the broadcast. Each illumination device that sendssuch a unicast message must receive an acknowledge to prevent suchillumination devices from resending the same message. Thus, the returnacknowledge is sent by controller back through the mesh network, also asa unicast message.

During the discovery phase, or discovery process, it is fairly timeconsuming to broadcast, receive and acknowledge back, and thereaftersend an acknowledge reply. However, since the discovery process happensinfrequently, and only generally during the configuration ofillumination devices during initial install, a time-consumptivediscovery process that could take multiple seconds is generallyacceptable to the user. However, when subsequently controlling thediscovered illumination devices, any time delay or lag, and especiallyany popcorn effect is to be avoided. Even a fraction of a second, insome instances, is noticeably annoying to a user when performing controlusing the subsequently described groupcast and aggregated acknowledgemechanism.

The discovery procedure, albeit relatively slow compared to the controlprocedure begins with a broadcast discovery message through which thatmessage is routed through possibly multiple hops to all of the variousnodes, including physical illumination devices 38 and physical keypads40. Each of those nodes, keypads and illumination devices unicast andacknowledge back to the remote controller 64, which must be routed as anacknowledge signal through the mesh network, whereupon the remotecontroller 64 then receives the acknowledge hopefully having all of theunique MAC addresses of the physical illumination devices by indicatinga blue light output from all such illumination devices and a blinkingphysical keypad of the discovered keypads.

FIG. 9 illustrates the grouping procedure, where a GUI on the remotecontroller 64 is used to group not only virtual illumination device 39icons, but also the physical illumination devices 38 based on any groupnamed by a user, or pre-existing groups with pre-existing scenesassigned thereto. FIG. 9 illustrates a GUI displayed on a remotecontroller 64 if the remote controller 64 has a screen similar to thatof a portable computer or phone. Upon the GUI, on a left hand portion ofthe GUI is an icon that represents either groups or keypads. When thegroups icon is selected, as indicated, a series of groups A, B, C, etc.,can appear. According to one embodiment a series of group icons 90appear. According to one embodiment, the group icons are not named untila user provides a name. Thus, for example, group A may be a name givento a group icon, or simply could be a default name given to a groupicon. The groups shown as icons on the GUI of the remote controller 64can have pre-defined names, such as the bedroom downlight or the bedroomnight stand. In the latter embodiment, those pre-defined names may alsohave pre-defined scenes or shows. For example, the bedroom downlight mayhave a pre-defined scene or show that is uniquely assigned to thedownlights, or illumination devices in the bedroom as content stored inthat group of illumination devices. The uniquely assigned scene/show ispreferably different from the pre-defined scene or show associated withthe bedroom night stand group of illumination devices, for example. Asshown in FIG. 9, after all of the illumination devices have beendiscovered and appear as virtual illumination devices 39, or icons, inthe right portion of the GUI 85, one or more illumination devices can begrouped by clicking on the virtual illumination device in the GUI andthat virtual illumination device icon 39, may blink or change to adifferent color. The corresponding physical illumination device or lamp38 within, for example, a bedroom will also change color, or blink, asshown by physical illumination devices blinking that corresponds to avirtual illumination device 39 icon blinking. In this fashion, the userwill then know the correspondence between virtual illumination deviceicons and physical illumination devices so that when he or she performsthe grouping procedure it is known which illumination device (virtualicon and physical) is assigned to each group as shown in FIG. 9, wherethe bedroom down illumination device 38 corresponding to virtualillumination device 39 is assigned to group A.

As an example, if there are three rooms with one keypad in each room(i.e., kitchen, living and bedroom), in the bedroom there may be two A20illumination devices on night stands and two PAR38 illumination devicesin the ceiling. The user may want to control these two groups ofphysical illumination devices independently so that two groups arecreated called bedroom downlights and bedroom night stands, and thesegroups are shown as another group name in groups 90 of the GUI 85. Inthe living room, there may be three A20 illumination devices and fourPAR38 illumination devices. The user may want to create three namedgroup icons 90 comprising one A20 on an end table next to a chair, twoA20s on either end of the couch, and four PAR38s in ceiling, so threegroups are created called living-downlight, living-end table-chair, andliving-end table couch. The named group icons can be named by the user,or can be pre-defined with pre-defined scenes and shows associatedtherewith. In the kitchen, there may be four PAR38s in the ceiling thatare controlled together, so a group called kitchen-downlight is created,or may pre-exist with an associated scene/show.

Using the example above, there are six groups of virtual illuminationdevice icons on the left side, with ten PAR38 lamp icons (virtualillumination devices) and five A20 lamp icons (virtual illuminationdevices) on the right side of the GUI. All the lights are still blue.When a lamp icon is clicked on by the user, the corresponding physicallamp and its associated MAC address changes color momentarily, as shownwhen, for example, the virtual illumination device icon is clicked on.The user will enter, for example, the bedroom and will note thecorresponding physical illumination device changes color or flashesindicating its correspondence to virtual illumination device. The userthen, for example, drags and drops the two virtual lamp icons into thegroup on the left called group A, or “bedroom-night stands,” forexample. This process can continue for the other groups where, forexample, the user can click on the PAR38 virtual lamp icons until thetwo in the bedroom are identified and then drags and drops those virtuallamp icons into the group called group B, or “bedroom-downlights,” forexample. When a virtual lamp icon is dropped into a group, theassociated physical lamp turns back to its default light color, forexample. The user can perform the same grouping procedure in the livingroom, kitchen, or throughout the structure.

At this point, all virtual illumination device icons on the right sideof the GUI are gone since they have been, for example, dragged anddropped into a corresponding group named group icon 90. Moreover, all ofthe physical illumination devices are producing white light. The nextstep is to configure the physical keypads in each room. Configuration ofthe virtual keypads using, for example, a mobile phone control devicewill be described later. However, at the present, configuration ofphysical keypads is described. When configuring the keypads, the usercan click on a different tab, for example, tab B, rather than tab A atthe top of the GUI. By clicking on another tab associated with keypads,the buttons on each keypad can be configured to produce a particularbrightness, color, spectrum setting and visual attribute setting for aparticular group of illumination devices. The device control procedureof configuring specific buttons on a physical keypad is shown in moredetail in reference to FIGS. 10a, 10b and 10 c.

For example, configuring a particular keypad begins by selecting thekeypad, as shown in FIG. 10a as the selection of the virtual keypad icon92 after clicking on the keypad icon in the left portion of the GUI 85.Once the virtual keypad icon 92 is identified, keypad icon 92 can beassigned to one or more group icons 90 to be named or a pre-definednamed group icon. Thereafter, as shown in FIG. 10b , the GUI 85 changesits display and presents a virtual keypad 92, with corresponding virtualtrigger buttons 98. Virtual buttons 98 can be replaced by a virtualslider, all of which fall within the category of a trigger. Five virtualbuttons are shown, however, there could be more or less buttons asneeded. A scene or show can be associated with a virtual scene/show icon100 selected and dragged and dropped onto the corresponding triggerbutton 98. In this fashion, each button on the virtual keypad 92 canoperate as a trigger slider. The longer a button is depressed, thegreater the slider position. Each trigger button can have associatedcontrol over one or more groups of physical illumination devices 38within a structure, and a corresponding scene or show assigned to eachof those group of illumination devices 38 by downloading correspondingcontent to the physical illumination devices 38. Assignment of a groupor a scene/show can also be performed from a dropdown menu, instead ofdrag and drop technique.

As an example, if there are two buttons that control thebedroom-downlight group and the bedroom-night stand group, the top twobuttons could control each of those groups. The user assigns aparticular color temperature, brightness or any visual attribute to eachof the various buttons and, in this case, the virtual buttons of thevirtual keypad 92. The bottom button, for example, can be assigned toall of the groups controlled by the corresponding physical keypad, andthe bottom button can be assigned to turn off all the lights associatedwith the various groups attributable to that keypad. The processdescribing grouping of buttons to a bedroom can be repeated for theliving room, the kitchen, and all of the remaining physical keypadswithin the structure. Grouping occurs through virtual keypadconfiguration that then corresponds to the appropriate physical keypads.Trigger buttons are selected and assigned to pre-defined or nonpre-defined groups of illumination devices, as well as scenes and showscontrolling those groups.

After programming into the various virtual buttons of the virtual keypaddisplayed on the controller 64 GUI, the corresponding group addressesand corresponding content of the assigned scenes and shows aredownloaded from the virtual keypad 92 to the corresponding physicalkeypad 40 of FIG. 1. The physical keypad 40 will operate identical tothe virtual keypad 92, in that touching any button corresponding to thefive buttons on the virtual keypad will send a groupcast control messageto the physical illumination devices being controlled by the physicalkeypad. Moreover, similar to the identification of physical illuminationdevices when performing grouping of virtual lamp icons, the physicalkeypad 40 associated with the virtual keypad 92 will blink when thatvirtual keypad is selected. For example, when virtual keypad 92 isselected within the GUI of controller 64, the corresponding physicalkeypad 40 a, 40 b, etc., will blink indicating to the user which keypadwithin the structure has been selected.

As shown in FIG. 10b , along with the five virtual buttons 98 of thevirtual keypad 92 are up/down buttons 104. The up/down trigger buttonscan be programmed in the virtual keypad 92 and have a correspondingsimilar programmed effect in the physical keypad 40. For example, once acorresponding button on the physical keypad 40 is actuated after havingbeen programmed using the virtual button on the GUI, the correspondinggroup of physical illumination devices turn on. The physical keypad 40or virtual keypad 92 may have buttons or touch lights corresponding tothe virtual trigger slider up/down buttons 104, which are operable onthe virtual keypad as well as on the physical keypad to adjustbrightness of the lights controlled by the last button pushed on thephysical/virtual keypad, for example. For instance, if the top button ofthe physical or virtual keypad associated with the bedroom sets thebedroom-downlight to red at half brightness, the up/down arrows wouldadjust the brightness of the bedroom-downlight after the top button ofthe physical/virtual keypad is pushed. The up/down arrows would controlthe brightness of the bedroom nightstands after, for example, anotherbutton associated with the group of bedroom nightstand was pushed. Whenan up/down arrow is pushed, a message is sent using groupcast addressingto the group of physical illumination devices associated with the keypadbutton. Alternatively, the up/down trigger 104 can control all of thegroups of illumination devices controllable by that keypad. For example,all groups associated with the virtual or physical keypad are dimmed orreverse-dimmed together, not just the ones controlled by the last button98 pushed. Also, as noted above, the trigger can include buttons 98 orthe up/down buttons 104. The duration at which a button 98 is depressedoperates as a trigger slider, or the appropriate up/down button 104among the group of five, for example, can also operate as a triggerslider for the last button 98 depressed or all buttons 98 assigned toall illumination devices within one or more rooms controlled by thosebuttons 98.

According to one embodiment, the group assigned to a virtual button on avirtual keypad, and thus to the physical button on the physical keypadcan also be assigned to a pre-defined scene or show through use of adrop down icon. The drop-down notes the pre-defined scene or showapplied to a group, and through the GUI of controller 64, the group andits corresponding scene or show is applied to, for example, a virtualbutton on the virtual keypad 92 which then downloads that group, sceneor show to a physical button on the corresponding physical keypad thatwas blinking to indicate it was selected for programming. After all ofthe buttons have been programmed to their corresponding pre-definedgroup name with pre-defined scene and show, or according to anotherembodiment, to any user-defined, and non pre-defined group name or sceneand show, the physical keypad can discontinue the blinking that occursduring the discovery/configuration process. Once the virtual keypad iconis dragged and dropped on the left side of the GUI screen, the user canthen enter a name for that keypad, like “bedroom_1”, for example. Toprogram the buttons on the virtual/physical keypad, the user selects thevirtual keypad on the left of the GUI screen 85, which is preferablypre-named something identifiable to the user.

According to one embodiment, if the scene and show was not pre-definedand assigned to a pre-defined group name, but instead is defined by auser to allow a button to take on any possible, substantially unlimitednumber of scenes or shows, a user can select the create scene or showbutton 106 as shown in FIG. 10b . A corresponding GUI will then appearon the remote controller 64 as shown in FIG. 10c . The GUI allows theuser to manually control any color temperature, brightness or visualattribute to be assigned, by clicking on the manual control 108. Themanual control can then bring up a black body curve 110 to allow a userto pick any color temperature along that black body curve 110, or tomanually select a visual attribute, color temperature (CCT) and/orbrightness, etc. using sliders 112 for each. Moreover, the user canassign times, either in increments or time of day 114, for eachattribute, color temperature or brightness to produce the automaticallychanging color temperature of a show. The time can be programmed to, forexample, daytime to automatically and dynamically change colortemperature throughout the day from sunrise to sunset. The show can alsoextend past sunset, to nighttime. The change in color temperature outputfrom the designated group or groups of illumination devices assigned thecreated show is automatic depending on shows stored in the correspondinggroup or groups of illumination devices. The change in color temperaturecan also be effectuated as a series of scenes triggered by a pluralityof times of day signals sent from a timer within the remote controller(either a virtual keypad 92 or a physical keypad 40). Thus, the remotecontroller 64 includes a real time clock that produces a plurality oftimes of day signals based on the calendar day and time of day duringdaylight hours. Those times of day signals can be synchronized viaconnection to a crystal oscillator, via connection to the Internet or toa satellite. Depending on which of the plurality of times of day signalsis sent, the color temperature output from the corresponding group ofillumination devices responds via a groupcast signals sent to thegrouped set of illumination devices MAC addresses. A different time ofday signal is sent at different times throughout the daylight hours totrigger a different color temperature output from the addressed group ofillumination devices. A user can therefore program the bedroom group ofillumination devices to operate to a different emulated sunlight than,for example, the kitchen group of illumination devices. Even though thesame time of day signal is sent to both the bedroom and kitchen groups(e.g., mid morning), the show stored in the bedroom illumination devicesmay produce a lower color temperature of 2300 Kelvin, or be off, whereasthe kitchen illumination devices may produce a higher color temperaturenearing 6000 Kelvin. Alternatively, the user can program the time of daysignals at different times for the kitchen versus the bedroom. Forexample, the sunrise time of day signal may be earlier in the bedroomthan in the kitchen. Having a separate remote controller for the kitchenverses the bedroom, and programming differently the timers in eachallows selective modification of the show and, thereafter selectivemanual override of each.

Turning now to FIG. 11, a graph is shown of the spectral sensitivity ofbrightness at different color wavelengths. Even though the illuminationdevices of the various wavelengths are equal in power from a physicalstandpoint, the visual system is not equally sensitive to differentwavelengths. For example, luminance or brightness can be expressed eventhough lights of equal power should produce the same effect at allspectral wavelengths, indeed, not all wavelengths appear equally bright.Photopic luminance is defined as L=c∫ P(λ) V (λ) d λ, where P isspectral power and V is the photopic spectral sensitivity of thestandard observer. As shown in FIG. 11, luminance can be expressed inthe fact that illumination devices of equal power but differentwavelengths do not appear equally bright to the standard observer.Further details about the relationship between color temperature as afunction of brightness and also time of day will be described later inreference to FIG. 15. According to one embodiment, however, it issufficient to acknowledge that the lower color temperatures are affectedmore so by changes in brightness and time of day than the higher colortemperatures. According to another embodiment, a variable brightnessthroughout the day yet with the same change in brightness can producethe same change to color temperature throughout the day. FIG. 12illustrates what occurs when a remote controller 64 such as avirtual/physical keypad receives user actuation upon, for example, atrigger slider to produce different intensity values sent to theinterface 52. The intensity values correspond to trigger positionvalues. The relationship between trigger position/status and lumenoutput has the characteristics shown in FIG. 12. The controller 54converts trigger position/status position to lumen output and colortemperatures through tables and interpolation. Those conversionfunctions are different at different times of day. Once the desiredlumen output and color temperatures are known, the controller 54calculates the drive currents needed for each LED chain. That valueapplied to all of the LED chains is a value of current or power neededto change the brightness output from all of the LED chains.

As noted in FIG. 12, changes in the slider movement to produce changesin intensity on the virtual/physical keypad, or on a triac dimmerassociated with the physical keypad, resulting brightness will change ina non-linear fashion. In other words, a non-linear relationship existsbetween the slider movement intensity output and brightness output. Thestorage medium 56 therefore contains a non-linear first mapping of theintensity value to the brightness value, so that each incremental changein the slider position on the virtual/physical keypad or dimmer willcorrespond to a mapped brightness value in accordance with a series ofpoints along the non-linear curve shown in FIG. 12. The map or plot ofintensity versus brightness non-linear curve is generally known as thebrightness dimcurve, and is mapped as a first mapping within the storagemedium. Movements of the trigger slider via user causes a resultingbrightness output, and the gradual movement and recording of brightnessoutput is then used to formulate the first mapping that is then storedin the storage medium 56 for subsequent use.

FIGS. 13a and 13b illustrate what occurs when a user actuates thetrigger at different times of day, those times of day being ones whichare sent from a timer within, for example, a remote controllerphysical/virtual keypad. A first time of day can be pre-sunrise,followed by a second time of day that triggers a sunrise event. Thepre-sunrise, sunrise, morning, and noon times of day each address adifferent dataset or content stored within the corresponding group orgroups of illumination devices. For example, a pre-sunrise time of dayoutput from a timer triggers a first content or dataset of the automaticshow, and which sends the appropriate ratio of currents to the LEDchains to produce a relatively low color temperature. Thus, the timertriggers a first content, which includes a relatively low lumen outputand color temperature. Prior to the automatic change occurring in theshow to a higher color temperature at, for example, a morning time ofday that would normally produce 3200 Kelvin, a manual adjustment on atrigger of, for example, a dimmer or the physical keypad will reduce thebrightness an amount 120 and, importantly, for that reduction inbrightness 120, the color temperature that would normally go to 3200Kelvin would be reduced to much less than 3200 Kelvin. The reduction inbrightness 120 and the significant reduction in color temperature canremain for a time out period, until the next time of day signal is sent,or the one following the next time of day signal, or when the trigger isactuated again to release the manual override mode.

The significant reduction in color temperature during manual overridedimming when a trigger is actuated (or increase in color temperatureduring reverse dimming) can occur without any fading. However, it isdesirable to fade in the automatic changes in color temperature thatoccur during the show and prior to manual override. Moreover, it isdesirable to have fewer times of day signals sent from the timer tominimize the amount of automatic fading in of color temperature changes.As shown in FIG. 13b , for example, an hour after sunrise a first timeof day signal is sent to increase color temperature in a plurality ofsteps 121, linearly 123, or exponentially 125 over a fixed time that ispreferably less than two hours and more preferably less than one hour.To minimize the number of times of day signals, there can be one moretime of day signal that decreases color temperature in a plurality ofsteps, linearly or exponentially over one hour or two hours an hourbefore sunset. Having possibly only two times of day signals and sendingthose signals twice a day would significantly reduce the amount ofcommunication needed to perform the show, and would lessen the amount ofcontent needed to be stored in one or more groups of illuminationdevices.

FIG. 13b also illustrates the same reduction in brightness 120 as thatshown in FIG. 13a if, for example, a user actuates the slider on thephysical keypad or dimmer the same amount as he or she did an hour aftersunrise (i.e., morning) in FIG. 13a . However, in FIG. 13b , the samereduction in brightness 120 produces significantly less reduction incolor temperature if the slider is actuated at noon time of day then atsunrise as shown in FIG. 13a . At noon, the color temperature that isautomatically and dynamically set at noon time of day to be, forexample, 6500 Kelvin, is reduced to slightly less than 6500 Kelvin (<6.5K Kelvin), and that reduction is far less than the reduction that wouldoccur in color temperatures during the morning or sunrise hours (<<<3.2K Kelvin). Accordingly, the effect of changes to brightness on the colortemperature depends on the time of day since, shown above, the spectralsensitivity is more profound at LED chains producing a lower colortemperature than on LED chains producing a higher color temperature.Even though the power or current supplied to all of the LED chainschanges the same amount based on changes to the intensity value, thecolor temperatures, for example, cool white having a predominance ofblue spectral output during noon time will change less than the spectraloutput of red predominantly produced during the sunrise or pre-sunrisehours.

A circadian show can be used to emulate sunlight at various times of theday and can continue in different groups of illumination devices withina structure. Yet if a defined task is needed for a certain group ofillumination devices, or the emulation needs to be changed to moreclosely resemble the outdoor daylight conditions, the circadian show canbe manually modified by a user to have a greater profound effect oncolor temperatures at certain times of day than other times of day. Asignificant benefit of the present invention is the greater effect ofchanges in brightness upon color temperatures one hour after sunrise andan hour before sunset than anytime therebetween, for example.

It is desirable to, even though dimming occurs manually, have a lessenedeffect on the color emulation at higher color temperature times than atlower color temperature times so that the circadian rhythm is notsignificantly disrupted even though a user manually changes thecircadian show that automatically occurs throughout the daylight hours.In others words, it is more advantageous to change the circadian show toa warmer color temperature during the warm white illumination outputtimes than during the cool white illumination output times that normallyoccur during peak sunlight hours. In this fashion, the manual adjustmentneeded to perform a task or to more closely resemble the actual outdoordaylight condition remains more consistent with the actual outdoordaylight condition. Warm white remains more so as warm white, whereascool white remains cool white, etc.

Reverse dimmer can also occur manually. During the nighttime hours, auser may actuate a trigger to manually override a nighttimeautomatically changing color temperature show that can be programmed tohave no illumination output regardless of the time of day signal sentor, in this case, time of nighttime day signal sent. For example, a usermay wish to actuate a trigger button or up/down button on the physicalkeypad of the bedroom to override the no illumination output show toincrease brightness and the color temperature within the group ofillumination devices within the bedroom. Reverse dimming advantageouslycauses a lower color temperature to be output to emulate incandescentlighting output that would normally occur when a user awakes from bedand turns on an incandescent light during nighttime hours. The manualoverride of reverse dimming that occurs during nighttime is similar todaytime in that a change in brightness will have a greater effect atlower color temperatures than at higher color temperatures. The presentinvention therefore applies to a circadian show that extends beyonddaytime, and the manual override equally applies to any change inbrightness and its effect on lower color temperatures more so thanhigher color temperatures.

Turning now to FIG. 14, storage medium 56 can contain content ordatasets associated with the illumination device containing the storagemedium 56. A group of illumination devices, possibly grouped accordingto the description shown in FIGS. 9 and 10, can each contain for thecorresponding group of illumination devices the same content. Forexample, the content in the color temperature settings for various timesof day 124, or various conditions that a sensor can sense, 126. Thevarious times of day 124 or sunlight conditions 126 stored in each of agroup of illumination devices having storage medium 56 are triggered bya time message in a case of time of day 124 or sensor readings in thecase of sunlight conditions 126.

As shown in FIG. 14, a time message can activate, or execute upon,content stored in storage medium 56 depending upon the value of thattime message, for example, is to execute upon noon time of day dataset124, then the time message would most likely be at or near noon timelocal to that timer within the remote controller. The timer or real timeclock with a remote controller 64 can send the appropriate time messageto address the appropriate content time of day 124. The time messagewould change the color output of the corresponding group of illuminationdevices having similarly stored time content or datasets. Alternatively,a button that would invoke a specific show, such as button 1 invokingshow A, would cause initiation of show A when button 1 is pushed. Thiswould cause the appropriate time message to be sent or, alternatively,timers can be found within each of the illumination devices thatautomatically change the content fetched at regular periodic intervalssimply by initiating the show A, for example. Whether the time messageis sent from the remote controller timer or the timer exists within thegroup of illumination devices based on the programmed show, aperiodically changing, automatically changing sequence of content ordatasets are executed upon by the control circuit controller 54 toemulate the changes in sunlight along the daytime locus from as littleas 2000 Kelvin during early sunrise to a maximum of over 6000 Kelvin atnoon time and then dropping back to less than 2000 Kelvin at sunset, forexample. According to an alternative embodiment, a sensor can beemployed similar to temperature sensor 58 to measure the sunlight,either interior to or exterior from the structure, and then based on thesensor readings automatically and dynamically change the content ordataset extracted and executed upon so that the sensed daylight can beemulated not only along the daytime locus but at any chromaticity pointor spectrum.

FIG. 15 is a graph of color and specifically color temperature or CCT,changing as a function of both time of day and brightness. The colortemperature for reasons described above automatically and dynamicallychanges throughout the day. As shown, the color temperature output fromthe plurality of LED chains automatically changes to replicate theactual sunlight conditions outside the structure and, for example,emulate the natural sunlight needed for treatment of circadian rhythmdisorders. During non-peak sunlight hours, such as pre-sunrise, sunrisein morning hours, as well as evening and sunset hours, the colortemperature can emulate sunrise and sunset hours along the daytimelocus. Preferably, during the morning and evening hours, the targetcolor temperatures are less than, for example, 3200 or 3000 Kelvin, andaround the noon-time hour the target color temperature can be as high as6000 or 6500 Kelvin. The 6000-6500 Kelvin can emulate blue sky noontime, whereas 3500 or less than 3000 Kelvin can emulate a mixture ofpredominantly yellow with some red morning sky or evening sky. FIG. 15illustrates different times of day (TOD), beginning with TOD1 throughTOD6, and possibly more.

FIG. 15 also shows a change in brightness from, for example, fullbrightness BR1 to a brightness less than full brightness, or BR2.According to one embodiment the brightness changes from one level BR1that is constant throughout the day to another level BR2 that is alsoconstant throughout the day. According to another embodiment, thebrightness changes from one level BR1 that varies throughout the day toanother level BR2 that also varies throughout the day. In eitherembodiment, the brightness changes from BR1 to BR2, causing an effect oncolor temperature is shown to depend on the time of day, with relativelylittle effect at TOD4, but greater effect at TOD1-3 and TOD5 and TOD6.The difference in color temperature for the same change in brightness isshown by the different arrows 130 and 132. Arrow 130 indicates a greaterchange in color temperature than arrow 132, yet the change in brightnessfrom BR1 to BR2 is the same. The change in brightness is effectuated bya change in intensity from the remote controller or dimmer. As thetrigger on the remote controller or dimmer is reduced to, for example,half its adjustment amount, the intensity can be reduced by half and,according to the first mapping of brightness to intensity shown in FIG.12, the brightness can be reduced non-linearly by an amount near halfthe previous brightness. If BR2 represents half brightness relative toBR1, color temperature changes not only as a function of brightness, butalso as a function of the time of day. At noon time, for example, eventhough the slider has moved indicating, for example, half brightness,the color temperature is relatively unaffected. This effect is of valuesince at noon time when a user wishes to perform a task and reduce thebrightness by manually adjusting the slider, it is desirable to placethe emulated sunlight at natural sunlight conditions of 6000 Kelvin orhigher even though the slider is moved. This ensures the emulateddaytime sunlight conditions after manual override still looks normal asto what is occurring outside. In other words, daytime natural sunlightconditions emulated by the plurality of LEDs remains near peak sunlighthours even though a user adjusts the brightness dimming along thedimcurve. Conversely, if a user adjusts the dimming along the dimcurveduring sunrise or morning hours, the color temperature will drop more sothan at noon for the advantageous reason that the actual sunlightconditions during those hours is more so in the warm white colortemperature anyway and any changes to dimming will retain even more sothe warm white conditions occurring outside.

FIG. 15 also shows in dashed line, according to a second embodiment,brightness changes from one level BR1 that varies throughout the day toanother level BR2′ that also varies throughout the day. In thisembodiment, any actuation of the trigger slider to invoke manualoverride will have the same effect in color temperature changethroughout the day, as shown by arrow 130 and arrow 132′ indicatingequal amounts of change at different times of day.

A major advantage of the preferred embodiment hereof is that when tasksare to be performed, for example, and brightness reduction occursthrough a dimcurve manually adjusted by a user, the emulated naturalsunlight condition nonetheless remains. Continuing the emulated sunlightconditions throughout waking hours and beyond, even when manual dimmingor reverse-dimming occurs is beneficial for psychological and aestheticreasons so that, for example, shortly after sunrise and before sunset,the lighting may be more desirable to be emulating incandescentlighting, such as halogen, etc. that produces more of a warm white colortemperature. The color emulation is therefore best suited forimplementation as an astronomical show because natural lighting mostdramatically changes based on whether the sun is up or down, andspecifically the path length of the sun. However, when performingcertain tasks, it is necessary to not couple brightness to a time-basedshow, and therefore a preferred embodiment allows the user to adjustbrightness as necessary. Changing brightness at noon time, for example,changes the brightness of the emulated sun at its peak sunlightcondition yet retains that peak sunlight or high color temperaturecondition. Conversely, changing brightness at morning or evening timesof day changes brightness of the emulated incandescent lighting, whereit is more desirable to produce even further lowering of colortemperature than at noon time. Therefore, the preferred embodimentshereof are not necessarily drawn to the automatic and dynamic changes incolor temperature throughout the day, but instead are drawn to the tasklighting conditions needed by a user periodically throughout the day,where brightness can be changed yet the effect on the color temperaturedepends upon the time of day at which the dimmer is actuated by theuser.

FIG. 16 illustrates the effect on color temperature, or CCT, whenbrightness is manually adjusted at different times in the morning andnoon hours (TOD3 and TOD4). Specifically FIG. 16 indicates a greaterchange in color temperature when brightness is manually changed from BR1(shown in solid line) to BR2 (shown in dashed line) during the morninghour of TOD3 versus the noon hour of TOD 4. At TOD3, when brightnesschanges from BR1 to BR2 shown by arrow 134, the color temperaturesubstantially drops. Yet, as shown by arrow 136 when brightness changesfrom BR1 to BR2, the color temperature does not drop nearly as much atnoon time TOD4 as morning TOD3. Of course, FIG. 16 is an example ofvarious TODs, and is not representative of possibly using only two TODs:an hour after sunrise and an hour before sunset, and possibly sunset ornighttime. Moreover, FIG. 16 does not illustrate TODs after sunset, orthe reverse dimming that can occur either during the daytime or afternighttime. Still further, FIG. 16 does not illustrate the fading in ofautomatic changes to color temperatures that would occur at each TOD.

FIG. 17 illustrates how user input from manual activation triggers, suchas a slider, on a triac dimmer or associated with a physical or virtualkeypad, produces intensity values fed into a brightness dimcurve module140 contains non-linear first mapping of the intensity value to thebrightness value within the storage medium, and maps a brightness valuecorresponding to the intensity value input to the dimcurve module 140. Acolor emulation module 142 receives the brightness value, as well astime of day messages, or TOD values from, for example, a timer 144. Thecombination of TOD values and brightness (BR) values are received by asecond mapping of color temperatures as a function of the time of day,as well as the brightness input. The color emulation module 142therefore performs the second mapping of the color temperature as afunction of the time of day as well as the brightness level inputthereto. Color emulation module 142 produces the corresponding colortemperature along the X/Y chromaticity graph and specifically along theblack body curve of color temperatures. Knowing the appropriatechromaticity, the chromaticity module 146 can comprise the controlcircuit and the LED driver circuits for controlling each of the LEDchains by sending the appropriate drive current to each of the pluralityof LED chains. Chromaticity module 146 therefore comprises the controland driving of the plurality of LED chains to produce the appropriateillumination from each of the plurality of LED chains. The combinationof the first and second mappings through the brightness dimcurve module140 and the color emulation module 142 produce the appropriate drivecurrents within the chromaticity module for maintaining sunlightemulation that is dependent upon the time of day as well as thebrightness changes.

It will be appreciated to those skilled in the art having the benefit ofthis disclosure that this invention is believed to provide an improvedillumination device, system and method that not only emulates sunlightthroughout the day, but as lighting tasks are needed, that emulation canbe maintained by advantageously dropping color temperature in themorning and evening hours more so than during noon time, for example.Further modifications in alternative embodiments of various aspects ofthe invention will be apparent to those skilled in the art in view ofthis description. It is intended, therefore, that the following claimsbe interpreted to embrace all such modifications and changes and,accordingly, the specification and drawings are to be regarded in anillustrative rather than a restricted sense.

1. An illumination device, comprising: a plurality of light emittingdiode (LED) chains; a driver circuit coupled to the plurality of LEDchains for automatically fading in a color temperature change from theLED chains depending on a time of day, wherein the automatically fadingcomprises fading in the color temperature change in a plurality of stepsover a fixed amount of time without user actuation of a trigger upon theremote controller, and wherein the plurality of steps increase the colortemperature an hour after sunrise; a control module coupled to thedriver circuit, said control module comprises: a controller coupled toreceive a change in intensity value from a remote controller that isremote from the controller and wirelessly or wired connected to thecontroller, and wherein the controller is coupled to receive the changein intensity value and, in response thereto, to produce a change in thecolor temperature output from the LED chains during a first time of dayrelative to a second time of day.
 2. The illumination device as recitedin claim 1, wherein the time of day comprises daytime.
 3. Theillumination device as recited in claim 1, wherein the time of daycomprises nighttime.
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 8. The illumination device as recited in claim 1, wherein thechange in intensity value is applied by user actuation of a trigger onthe remote controller.
 9. The illumination device as recited in claim 1,further comprises a dimmer coupled to AC mains, and wherein the changein intensity value is applied by user actuation of a trigger on thedimmer.
 10. The illumination device as recited in claim 1, wherein thechange in intensity value corresponds to a fixed change in brightnessapplied to the LED chains to produce a greater change in colortemperature output from the LED chains during the first time of day thanduring the second time of day.
 11. The illumination device as recited inclaim 1, wherein the change in intensity value corresponds to a variablechange in brightness applied to the LED chains to produce an equalchange in color temperature output from the LED chains during the firsttime of day as that of the second time of day.
 12. The illuminationdevice as recited in claim 11, wherein the variable change in brightnessoccurs as a function of the time of day.
 13. (canceled)
 14. (canceled)15. (canceled)
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 17. (canceled)
 18. (canceled) 19.(canceled)
 20. (canceled)
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 22. (canceled)23. (canceled)
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 26. (canceled) 27.(canceled)
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 31. Anillumination device, comprising: a plurality of light emitting diode(LED) chains; a driver circuit coupled to the plurality of LED chainsfor automatically fading in a color temperature change from the LEDchains depending on a time of day, wherein the automatically fadingcomprises fading in the color temperature change linearly over a fixedamount of time without user actuation of a trigger upon the remotecontroller, and wherein the linear change increases the colortemperature an hour after sunrise; a control module coupled to thedriver circuit, said control module comprises: a controller coupled toreceive a change in intensity value from a remote controller that isremote from the controller and wirelessly or wired connected to thecontroller, and wherein the controller is coupled to receive the changein intensity value and, in response thereto, to produce a change in thecolor temperature output from the LED chains during a first time of dayrelative to a second time of day.
 32. The illumination device as recitedin claim 31, wherein the time of day comprises daytime.
 33. Theillumination device as recited in claim 31, wherein the time of daycomprises nighttime.
 34. The illumination device as recited in claim 31,wherein the change in intensity value is applied by user actuation of atrigger on the remote controller.
 35. The illumination device as recitedin claim 31, further comprises a dimmer coupled to AC mains, and whereinthe change in intensity value is applied by user actuation of a triggeron the dimmer.
 36. The illumination device as recited in claim 31,wherein the change in intensity value corresponds to a fixed change inbrightness applied to the LED chains to produce a greater change incolor temperature output from the LED chains during the first time ofday than during the second time of day.
 37. The illumination device asrecited in claim 31, wherein the change in intensity value correspondsto a variable change in brightness applied to the LED chains to producean equal change in color temperature output from the LED chains duringthe first time of day as that of the second time of day.
 38. Theillumination device as recited in claim 37, wherein the variable changein brightness occurs as a function of the time of day.